1. Field of the Invention
This invention involves novel polymerizable monomers having pendent ester groups and polymers prepared from those monomers. The monomers have the structure: ##STR2## wherein R.sup.1 is hydrogen or methyl; R.sup.2 R.sup.3 and R.sup.4 are each independently lower alkyl of 1 to about 4 carbons; and Z is nothing or is a divalent alkyl radical having 1 to about 20 carbon atoms. Preferred divalent alkyl radicals are methylene chains--(--CH.sub.2 --).sub.n --wherein n is 1 to 20.
This invention also relates to polymers obtained by polymerizing, under free radical addition polymerization conditions, (i) the unsaturated ester monomer of this invention; and (ii) optionally, at least one other unsaturated monomer copolymerizable with the unsaturated ester monomer. The monomers are also useful as reactive diluents and as precursors for acid and/or anhydride-functional monomers.
2. Description of the Prior Art
Unsaturated, polymerizable esters, such as butyl acrylate, methyl methacrylate, methyl crotonate, or ethyl tiglate and polymers or copolymers incorporating these materials are known in the art. By the selection of one or more of these esters, the characteristics of a polymer may be tailored to provide a desired glass transition temperature, hardness, flexibility or other desired property. The prior art has not, however, taught polymers obtained by the polymerization of the novel styrene-based ester monomers of this invention.